1. Field of the Invention
The present invention relates to an ink tank provided with a semiconductor element having functions of detecting environmental information of the surroundings to communicate the information to the outside and display the same, or having functions of detecting information inside an ink tank (e.g., an ink residual amount) using a semiconductor element to communicate the information to the outside and display the same.
In addition, the present invention relates to an ink jet recording apparatus such as a facsimile machine, a printer and a copying machine to which the ink tank is detachably mountable.
2. Related Background Art
Conventionally, in an ink jet recording apparatus for printing an image on a sheet with dot patterns by moving a carriage, which is provided with a recording head, in a printing direction while jetting ink from a plurality of jet nozzles provided in the recording head, an ink tank containing ink for recording is provided and the ink in the ink tank is supplied to the recording head via an ink supply line. Therefore, an ink residual amount detection apparatus, with which a residual amount of the ink in the ink tank is detected, has been practically used, and a variety of ink residual amount detection apparatuses have been proposed.
For example, according to Japanese Patent Application Laid-open No. 6-143607, two (a pair of) electrodes 702 are disposed on an internal surface of the bottom of an ink tank 701 that is filled with nonconductive ink, and a float body 703, on which electrodes 704 opposing the electrodes 702 are disposed, floats in ink contained in the ink tank 701 as shown in FIGS. 26A to 26C of the patent application. The patent application discloses that the two electrodes 702 are connected respectively to a detecting unit (not shown) for detecting a conduction state of both the electrodes, and when detecting the conductance of both the electrodes, the detecting unit outputs a residual ink error signal indicating that no ink is left in the ink tank 701 and stops operations of an ink jet recording head 705.
In addition, Japanese Patent No. 2947245 discloses an ink cartridge 805 for an ink cartridge 805 for ink jet printer with a configuration in which a lower part is formed in a funnel-shape toward a bottom surface, two electric conductors 801 and 802 are provided on the bottom surface and a metal ball 804 having specific gravity smaller than that of ink 803 is provided inside. In such a configuration, when the ink 803 is consumed and decreases, the liquid level of the ink 803 is lowered. As the liquid level of the ink 803 is lowered, the position of the metal ball 804 floating on the liquid level is also lowered. When the liquid level of the ink 803 is lowered to the position of the bottom surface of the ink cartridge housing, the metal ball 804 contacts the two electric conductors 801 and 802. Then, since the electric conductors 801 and 802 continue each other, an electric current flows between them. If the flow of the current is detected, an ink end state can be detected. If the ink end state is detected, information indicating the ink end state is communicated to a user.
Configurations for detecting an ink residual amount in an ink tank as represented by the conventional art disclosed in the above-mentioned patent and patent application are known. In the above-mentioned configurations, it is necessary to dispose electrodes for detection in the ink tank such that information and a state are detected and communicated by directly contacting elements themselves such as electrodes and a float body or electric conductors and a metal ball. In addition, since the ink residual amount is detected by a conduction state between the electrodes, there is a restriction on ink to be used as indicated by the fact that a metal ion cannot be used as an ink component, or the like.
In addition, only the ink residual amount can be detected and the other information on the inside of the tank cannot be found from the outside in the above-mentioned configurations. For example, pressure information inside the ink tank, variations of a physical property of the ink, or the like are parameters that are important for always operating an ink jet head with a stable discharge amount. Thus, a tank is desired which can inform, on a real time basis, an ink jet recording apparatus in the outside of a pressure inside the tank that varies every moment in accordance with the consumption of the ink in the tank, or can communicate the variations of the physical property of the ink to the outside.
Moreover, an ink tank is desired which does not only unilaterally informs the outside of information detected in the ink tank but also can execute bidirectional exchanges of information such as returning inside information in response to an inquiry from the outside.
In developing an ink tank such as those described above, inventors of the present invention took notice of a ball semiconductor of Ball Semiconductor, Inc. in which a semiconductor integrated circuit was formed on a spherical surface of a silicon ball with a diameter of one millimeter. Since the ball semiconductor had a spherical shape, it was expected that, if this ball semiconductor was contained in the ink tank, the detection of surrounding environmental information and the bidirectional exchanges of information with the outside could be performed extremely efficiently compared with a flat-shaped one. However, when the inventors searched an ink tank having such functions, it was found that only a technology for connecting ball semiconductors by electric wiring as disclosed in U.S. Pat. No. 5,877,943 is existed, and that it is necessary to develop an element itself having the above-mentioned functions. In addition, in order to make this element effectively applicable to the ink tank, there were problems that should be cleared. One of the problems is supply of electricity for activating the element contained in the tank. If a power source for activating the element is provided in the ink tank, the tank becomes larger, or even if the power source is provided outside the tank, wiring is necessary between the power source and the element. As a result, since manufacturing costs of the tank increases and a tank cartridge becomes expensive, a user has to activate the element from the outside without contacting it or has to activate the element by directly contacting it.
In addition, it is not conventionally known that a user communicates information between two elements disposed in remote places without contacting them or communicates with and controls a configuration that is provided with, for example, a plurality of pairs consisting of two elements.